GUVI Biblio

Comments on “A new method to subtract dayglow for auroral observation of SSUSI in LBH ranges based on the improved AURIC” by Wang et al. (2021)

A paper A new method to subtract dayglow for auroral observation of SSUSI in LBH ranges based on the improved AURIC reports a new method to estimate the dayglow intensities in DMSP/SSUSI LBH bands using an improved AURIC model. It is claimed that the new method offers a better alternative than the SSUSI operational algorithm which uses a data based table. The paper showed a few examples and compared them with SSSUI operational results. The comparison indicated that the new method didn t offer any improvement and provided net ...

Zhang, Yongliang; Paxton, Larry; Schaefer, Robert;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on: mar

YEAR: 2022     DOI: 10.1016/j.jastp.2022.105833

AURORA; dayglow; far ultraviolet emission

Thermospheric density enhancement and limb O 130.4 nm radiance increase during geomagnetic storms

We explore a connection between thermospheric density enhancement and increase in thermospheric O 130.4 nm radiance. We observe TIMED/GUVI enhancements in the limb 130.4 nm radiances at ∼400 and ∼520 km on the dayside during four intense geomagnetic storms in 2003 and 2004. The enhancements were well correlated with Dst and CHAMP total neutral density at 400 km which represents O density as O is the dominant species at those altitudes. At the 400 and 520 km altitudes, O 130.4 nm emissions are mostly created by two ...

Zhang, Yongliang; Paxton, Larry; Schaefer, R.;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on: mar

YEAR: 2022     DOI: 10.1016/j.jastp.2022.105830

FUV emission; Geomagentic storms; neutral density; thermosphere

Simultaneous Detection of Signatures of Conjugate Photoelectrons in the Ionosphere and Thermosphere

We investigate the impact of conjugate photoelectrons (CPEs) on the topside (∼600 km altitude) ionosphere at low and midlatitudes using measurements of the ion temperature, density, and composition from the first Republic of China satellite during a period of the high to moderate solar activity (March 1999 to June 2004). Elevated ion temperatures and densities are observed in the dark Northern American-Atlantic sector during the December solstice and in the Australian sector during the June solstice. The oxygen ion fractio ...

Kil, Hyosub; Paxton, Larry; Schaefer, Robert;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2022     DOI: 10.1029/2021JA030121

airglow; conjugate photoelectron; ion density; ion temperature

Thermospheric density enhancement and limb O 130.4 nm radiance increase during geomagnetic storms

Zhang, Yongliang; Paxton, Larry; Schaefer, R;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on:

YEAR: 2022     DOI:

Comments on “A new method to subtract dayglow for auroral observation of SSUSI in LBH ranges based on the improved AURIC” by Wang et al.(2021)

Zhang, Yongliang; Paxton, Larry; Schaefer, Robert;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on:

YEAR: 2022     DOI:

Increased Sensitivity FUV Spectrographic Imager

Schaefer, RK; Paxton, LJ; Zhang, Y; Kil, H; Liou, K;

Published by:       Published on:

YEAR: 2022     DOI:

Hemispheric Asymmetry in the Auroral Ionosphere-Thermosphere System

Liou, K; Zhang, Y-L; Paxton, LJ; Kil, H; Schaefer, R;

Published by:       Published on:

YEAR: 2022     DOI:

Revisiting the November 2004 Superstorm: Lessons from the TIMED/GUVI Limb Observation

We revisited the November 2004 superstorm by analyzing data from TIMED/GUVI, a FUV spectrograph imager. The GUVI 135.6 nm limb radiances at 520-km tangent altitude are mainly due to the O+ and electron radiative recombination and represent the daytime ionosphere density at the altitude. The 135.6 nm radiances clearly showed a signature of ionospheric equatorial arcs and their variations during the November 2004 magnetic superstorm. When an intense eastward Interplanetary Electric Field (IEF) occurred, the dayside equatorial ...

Zhang, Yongliang; Wang, Wenbin; Paxton, Larry; Schaefer, Robert; Huang, Chaosong;

Published by: 44th COSPAR Scientific Assembly. Held 16-24 July      Published on:

YEAR: 2022     DOI:

Thermospheric conditions associated with the loss of 40 Starlink satellites

We analyzed far ultraviolet data from Defense Meteorological Satellite Program (DMSP)/Special Sensor Ultraviolet Spectrographic Imager (SSUSI) and Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED)/Global Ultraviolet Imager (GUVI) and found significant changes in the thermospheric density and composition during the 3–5 February 2022 storm when 40 Starlink satellites started to re-enter the atmosphere associated with increased neutral drag at an altitude around 210 km. The standard NRLMSISE-00 model predicts ...

Zhang, Yongliang; Paxton, Larry; Schaefer, Robert; Swartz, William;

Published by: Space Weather      Published on:

YEAR: 2022     DOI: 10.1029/2022SW003168

Exploring the Upper Atmosphere

In this chapter, we describe how we can understand the state of the upper atmosphere (the ionosphere, thermosphere, and aurora) using optical observations and how one produces a global view of the Earth s upper atmosphere from optical remote sensing, especially using far ultraviolet (FUV) wavelengths, to advance our understanding of the near Earth space environment. We examine the choice of optical signatures, the basic science behind the signatures, and the techniques for observations. Examples of the technique as applied t ...

Paxton, Larry; Zhang, Yongliang; Kil, Hyosub; Schaefer, Robert;

Published by:       Published on:

YEAR: 2021     DOI: 10.1002/9781119815631.ch23

Earth space environment; far ultraviolet wavelengths; high-latitude regions; optical remote sensing; solar wind; upper atmosphere

Far Ultraviolet Hyperspectral Imager: NASA's TIMED/GUVI and DMSP SSUSI

Paxton, Larry; Zhang, Yongliang; Schaefer, Robert; Kil, Hyosub; Wolven, Brian; Romeo, Giuseppe; Yonker, Justin;

Published by:       Published on:

YEAR: 2021     DOI:

Signatures of conjugate photoelectrons in the ionosphere and thermosphere

Kil, Hyosub; Paxton, Larry; Schaefer, Robert; Huba, Joseph;

Published by:       Published on:

YEAR: 2021     DOI:

Exploring the Upper Atmosphere: Using Optical Remote Sensing

Paxton, Larry; Zhang, Yongliang; Kil, Hyosub; Schaefer, Robert;

Published by: Upper Atmosphere Dynamics and Energetics      Published on:

YEAR: 2021     DOI:

Ionospheric and thermospheric contributions in TIMED/GUVI O 135.6 nm radiances

Zhang, Yongliang; Paxton, Larry; Schaefer, Robert;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2021     DOI:

Large Electron Densities in the Early Morning Equatorial Ionosphere Observed with UV Instruments from Space

Schaefer, Robert; Paxton, Larry; Zhang, Yongliang; Kil, Hyosub; Romeo, Giuseppe; Wolven, Brian; Yonker, Justin;

Published by:       Published on:

YEAR: 2021     DOI:

The Far Ultraviolet Signatures of Conjugate Photoelectrons Seen by the Special Sensor Ultraviolet Spectrographic Imager

This study investigates the origin of anomalous far ultraviolet emissions observed at night at the subauroral region by the Special Sensor Ultraviolet Spectrographic Imager on board the Defense Meteorological Satellite System-F16 satellite. The global distribution of the anomalous emission is derived using the measurements of the oxygen atom 130.4-nm emission in 2017. Our results show the extension of the anomalous emission from high latitudes to middle latitudes in the Northern American-Atlantic sector during the Decembe ...

Kil, Hyosub; Schaefer, Robert; Paxton, Larry; Jee, Geonhwa;

Published by: Geophysical Research Letters      Published on: 01/2020

YEAR: 2020     DOI: 10.1029/2019GL086383

conjugate photoelectron; far ultraviolet emission; thermosphere; remote sensing data

The far ultraviolet signatures of conjugate photoelectrons seen by the Special Sensor Ultraviolet Spectrographic Imager

Kil, Hyosub; Schaefer, Robert; Paxton, Larry; Jee, Geonhwa;

Published by: Geophysical Research Letters      Published on:

YEAR: 2020     DOI:

Estimation of solar EUV flux from TIMED/GUVI data

Zhang, Yongliang; Paxton, Larry; Schaefer, Robert;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on:

YEAR: 2020     DOI:

A comparison of thermospheric FUV radiance and composition from TIMED, GOLD and ICON

Zhang, Y; Paxton, LJ; Schaefer, RK; Eastes, R; McClintock, WE; Immel, TJ;

Published by:       Published on:

YEAR: 2020     DOI:

Deriving Thermospheric Temperature From Observations by the Global Ultraviolet Imager on the Thermosphere Ionosphere Mesosphere Energetics and Dynamics Satellite

This paper reports a preliminary result for estimating thermospheric temperature around 155 km from the N₂ Lyman-Birge-Hopfield bands observed by TIMED/Global Ultraviolet Imager (GUVI). Atmospheric Ultraviolet Radiance Integrated Code model (Strickland et al., 1999, https://doi.org/10.1016/S0022-4073(98)00098-3) calculations indicate that the intensity ratio in the N₂ Lyman-Birge-Hopfield (0,0) and (1,0) bands at 144.5- ...

Zhang, Yongliang; Paxton, Larry; Schaefer, Robert;

Published by: Journal of Geophysical Research: Space Physics      Published on: 06/2019

YEAR: 2019     DOI: 10.1029/2018JA026379

Addressing O2R with the SSUSI Operational Space Sensor: Lessons Learned

Schaefer, Robert; Paxton, Larry; Romeo, Giuseppe; Kil, Hyosub; Wolven, Brian; Zhang, Yongliang;

Published by:       Published on:

YEAR: 2019     DOI:

Storm-time variations in the thermsopheric density, composition and temperature.

Zhang, Yongliang; Paxton, Larry; Schaefer, Robert;

Published by:       Published on:

YEAR: 2019     DOI:

Storm-time variations of atomic nitrogen 149.3 nm emission

Net radiances of atomic nitrogen emission line (N-149.3 nm) from the thermosphere are extracted from the FUV spectra observed by TIMED/GUVI on dayside at ...

Zhang, Y.; Paxton, L.J.; Morrison, D.; Schaefer, B.;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on: 04/2018

YEAR: 2018     DOI: 10.1016/j.jastp.2018.01.023

SSUSI and SSUSI-Lite: Providing space situational awareness and support for over 25 years

Paxton, Larry; Schaefer, Robert; Zhang, Yongliang; Kil, Hyosub; Hicks, John;

Published by: Johns Hopkins APL Technical Digest      Published on:

YEAR: 2018     DOI:

Nightime Ionosphere Climatology as observed by TIMED/GUVI

Schaefer, Robert; Edenbaum, Harris;

Published by:       Published on:

YEAR: 2018     DOI:

Ionospheric-thermospheric UV tomography: 3. A multisensor technique for creating full-orbit reconstructions of atmospheric UV emission

We present the Volume Emission Rate Tomography (VERT) technique for inverting satellite-based, multisensor limb and nadir measurements of atmospheric ultraviolet emission to create whole-orbit reconstructions of atmospheric volume emission rate. The VERT approach is more general than previous ionospheric tomography methods because it can reconstruct the volume emission rate field irrespective of the particular excitation mechanisms (e.g., radiative recombination, photoelectron impact excitation, and energetic particle pre ...

Hei, Matthew; Budzien, Scott; Dymond, Kenneth; Nicholas, Andrew; Paxton, Larry; Schaefer, Robert; Groves, Keith;

Published by: Radio Science      Published on: 07/2017

YEAR: 2017     DOI: 10.1002/2015RS005887

Far ultraviolet instrument technology

The far ultraviolet (FUV) spectral range (from about 115 nm to 180 nm) is one of the most useful spectral regions for characterizing the upper atmosphere (thermosphere and ionosphere). The principal advantages are that there are FUV signatures of the major constituents of the upper atmosphere as well as the signatures of the high-latitude energy inputs. Because of the absorption by thermospheric O₂, the FUV signatures are seen against a \textquotedblleftblack\textquotedblright background, i.e., one that is not ...

Paxton, Larry; Schaefer, Robert; Zhang, Yongliang; Kil, Hyosub;

Published by: Journal of Geophysical Research: Space Physics      Published on: 01/2017

YEAR: 2017     DOI: 10.1002/jgra.v122.210.1002/2016JA023578

A New More Accurate Calibration for TIMED/GUVI

Schaefer, RK; Aiello, J; Wolven, BC; Paxton, LJ; Romeo, G; Zhang, Y;

Published by:       Published on:

YEAR: 2017     DOI:

TIMED/GUVI Observations of Aurora, Ionosphere, Thermosphere and Solar EUV Variations

Zhang, Yongliang; Paxton, Larry; Schaefer, Robert;

Published by:       Published on:

YEAR: 2017     DOI:

Monitoring Geospace Variations Through Remote Sensing III Posters

Zhang, Yongliang; Paxton, Larry; Sibeck, David; Schaefer, Robert;

Published by:       Published on:

YEAR: 2017     DOI:

TIMED GUVI: Recent Progress and Future Challenges in the Ionosphere, and Thermosphere System Coupling

Schaefer, Robert; Paxton, Larry; Zhang, Yongliang;

Published by:       Published on:

YEAR: 2016     DOI:

Validating Local Responses in OVATION Prime-2013 and OVATION-SM with DMSP SSUSI

Mitchell, Elizabeth; Schaefer, Robert; Paxton, Larry;

Published by:       Published on:

YEAR: 2016     DOI:

Structure and Variability in the Ionosphere using DMSP/SSUSI and TIMED/GUVI Data

Bruntz, Robert; Paxton, Larry; Kil, Hyosub; Schaefer, Robert; Zhang, Yongliang; Miller, Ethan;

Published by:       Published on:

YEAR: 2016     DOI:

Observation and Modeling of the South Atlantic Anomaly in Low Earth Orbit Using Photometric Instrument Data

Selby, Christina; Paxton, LJ; Schaefer, RK; Ogorzalek, B; Romeo, G; Wolven, B; Hsieh, SY;

Published by:       Published on:

YEAR: 2016     DOI:

NASA Timed Guvi and Dmsp Ssusi Observations of the St. Patricks Day Storm of

Paxton, Larry; Zhang, Yongliang; Kil, Hyosub; Mitchell, Elizabeth; Schaefer, Robert;

Published by: 41st COSPAR Scientific Assembly      Published on:

YEAR: 2016     DOI:

SSULI/SSUSI UV tomographic images of large-scale plasma structuring

Hei, Matthew; Budzien, Scott; Dymond, Kenneth; Paxton, Larry; Schaefer, Robert; Groves, Keith;

Published by:       Published on:

YEAR: 2015     DOI:

UV Observations of Hemispheric Asymmetry

Schaefer, Robert; Paxton, Larry; Wolven, Brian; Zhang, Yongliang; Romeo, Giuseppe;

Published by:       Published on:

YEAR: 2015     DOI:

GUVI and SSUSI Observations of the St. Patrick's Day Storms

Paxton, Larry; Schaefer, Robert; Zhang, Yongliang; Bust, Gary; Kil, Hyosub;

Published by:       Published on:

YEAR: 2015     DOI:

Interannual Variability of the Atmospheric Tides over South Pole from a Decade of Meteor Wind Observations

Paxton, LJ; Schaefer, RK; Zhang, Y; Bust, GS; Kil, H;

Published by:       Published on:

YEAR: 2014     DOI:

A comprehensive empirical model of the ionospheric conductivity derived from SSUSI/GUVI, SuperMAG and SuperDARN data.

Gjerloev, Jesper; Schaefer, Robert; Paxton, Larry; Zhang, Yongliang;

Published by:       Published on:

YEAR: 2014     DOI:

Ionospheric Data Assimilation from a Data Provider's Perspective

Schaefer, Robert; Paxton, Larry; Bust, G; Zhang, Yongliang; Romeo, Giuseppe; Comberiate, Joseph; Gelinas, Lynette;

Published by:       Published on:

YEAR: 2014     DOI:

EMIC Wave Induced Radiation Belt Losses and Proton Aurora

Erlandson, Robert; Paxton, Larry; Zhang, Yongliang; Schaefer, Robert;

Published by:       Published on:

YEAR: 2014     DOI:

Specification of Auroral Ionospheric Conductances Using SSUSI and GUVI UV Imagery

Paxton, Larry; Zhang, Yongliang; Schaefer, Robert; Weiss, Michele; Miller, Ethan;

Published by:       Published on:

YEAR: 2014     DOI:

Operational Space Weather Needs-Perspectives from SEASONS 2014

Comberiate, Joseph; Kelly, MA; Paxton, Larry; Schaefer, Robert; Bust, Gary; Sotirelis, Thomas; Fox, Nicola;

Published by:       Published on:

YEAR: 2014     DOI:

Establishing the connection between crowd-sourced data and decision makers

Paxton, Larry; Swartz, W; Strong, Shadrian; Nix, MG; Schaefer, Robert; Weiss, Michele;

Published by:       Published on:

YEAR: 2014     DOI:

Updated Global Data from the Guvi Instrument: New Products, Updated Calibration, and a New Web Interface

Schaefer, Robert; Paxton, Larry; Romeo, Giuseppe; Wolven, Brian; Zhang, Yongliang; Comberiate, Joseph;

Published by:       Published on:

YEAR: 2014     DOI:

Multi-Instrument Observations at High Latitudes

Miller, E; Paxton, L; Schaefer, RK; Weiss, M; Wolven, BC; Zhang, Y;

Published by:       Published on:

YEAR: 2013     DOI:

Observing the mid-and low-latitude ionosphere-global UV remote sensing

Paxton, LJ; Kil, H; Miller, ES; Comberiate, J; Schaefer, RK; Zhang, Y; Team, GUVI; , others;

Published by:       Published on:

YEAR: 2013     DOI:

Observing the Edge of the Inner Radiation Belt: the South Atlantic Anomaly Seen with Photometers in Low Earth Orbit

Schaefer, RK; Wolven, BC; Paxton, L; Romeo, G; Selby, C; Hsieh, SW;

Published by:       Published on:

YEAR: 2013     DOI:

UV Remote Sensing Data Products-Turning Data Into Knowledge

Weiss, M; Paxton, L; Schaefer, RK; Comberiate, J; Hsieh, SW; Romeo, G; Wolven, BC; Zhang, Y;

Published by:       Published on:

YEAR: 2013     DOI: